chaos-pr-bundle-fuzzer: make PR count deterministic at 5 and expand merge-tree strategy coverage

[Copilot]

✨ Enhancement

The chaos-pr-bundle-fuzzer prompt currently allows variable PR counts and under-specifies complex history scenarios. This update makes each run exercise exactly 5 PR scenarios and explicitly drives complex merge-tree paths (multi-parent, octopus, diverged histories) while improving ledger balancing expectations.

• Deterministic run shape

  • Updated hard requirement from “at most 5 PRs” to exactly 5 PRs per run.
  • Replaced randomized PR-count planning (1..5) with a fixed 5-scenario plan.

• Expanded merge-tree edge coverage

  • Extended strategy mix to explicitly include:
    • multi-parent merge commits
    • octopus merges
    • diverged history reconciliation

• Better cross-run strategy balancing

  • Refined ledger guidance to balance under-tested strategies across simple and complex categories, not just fuzzy rotation.

# Before
- Random PR count between 1 and 5.
- Random strategy mix (... line-ending variant).

# After
- Always generate 5 PR scenarios.
- Random strategy mix (..., multi-parent merge commit, octopus merge, diverged history reconciliation).
- Prefer under-tested strategies while balancing simple and complex categories across runs.

[Copilot]

Pull request overview

Updates the chaos-pr-bundle-fuzzer workflow prompt to make each run deterministically generate five PR scenarios and to broaden the scenario strategy mix toward more complex merge-history shapes.

Changes:

• Changed the hard requirement from “at most 5 PRs” to “exactly 5 PRs” per run.
• Replaced randomized PR-count planning (1..5) with a fixed plan of 5 scenarios.
• Expanded the strategy mix and adjusted ledger guidance to balance under-tested strategies across simple vs complex categories.

Show a summary per file

File	Description
.github/workflows/chaos-pr-bundle-fuzzer.md	Makes PR count deterministic at 5 and expands/adjusts strategy selection guidance to target more complex merge-tree histories.

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Comments suppressed due to low confidence (2)

.github/workflows/chaos-pr-bundle-fuzzer.md:67

• “balancing simple and complex strategy categories” is introduced here but the document never defines which strategies are considered simple vs complex or how to record this in the ledger. Please define the categories (or tag each strategy with a category) so the balancing instruction is actionable and consistent across runs.

3. Prefer strategies that were under-tested in previous runs while balancing simple and complex strategy categories across runs.

.github/workflows/chaos-pr-bundle-fuzzer.md:66

• The term “multi-parent merge commit” is ambiguous because all merge commits have multiple parents; it’s unclear whether this means a non-fast-forward 2-parent merge commit or a >2-parent merge (which overlaps with “octopus merge”). Consider renaming/clarifying the strategy label to match the intended history shape.

   - Random strategy mix (single commit, two commits, amend, staged subset, minor rename, line-ending variant, multi-parent merge commit, octopus merge, diverged history reconciliation).

• Files reviewed: 1/1 changed files
• Comments generated: 2